Senna silvestris var. guaranitica (Chodat & Hassl.) H.S.Irwin & Barneby

Family

Caesalpiniaceae

Scientific Name

Senna silvestris var. guaranitica (Chodat & Hassl.) H.S.Irwin & Barneby

Type

Lectoholotypus, Hassler 5338, G! isotypus, NY! paratypi, Hassler 5889, G, NY!

Synonyms

Cassia guaranitica Chodat & Hassl., Cassia guaranitica f. latifolia Chodat & Hassl.

Description

Variety Description - Shrub or subshrub at anthesis 1-3 m, either glabrous except for puberulent pulvinules or (rarely) the stems and lower face of lfts pilosulous with straight ascending hairs; lvs 13-28 cm; lfts (7-)8-11(-12) pairs, the largest (near or beyond middle of lf) ovate 4-7 X 1.4-2.8 cm, 2.3-3.3 times as long as wide, at base deeply cordate, the sinus often as deep as the short pulvinule (1.5-2.5 mm), 8-10.5 mm; petals 12-20 mm; ovary glabrous; ovules 26-32; body of pod 8-14 X (1-)1.2-1.7 cm, the locules 1-seriate.--Collections: 12.

Distribution and Ecology - Cerrado, and becoming weedy in roadside thickets, 200-550 m, locally abundant in the triangle formed by the parallel 19°S, Rio Paraguai and Rio Parana in s. Mato Grosso and s.-e. Paraguay.

Discussion

The distinct facies of Cassia guaranitica is due entirely to the relatively small size of the stiffly chartaceous lustrous leaflets which, because of their cordate base and short pulvinule, appear to stand subsessile against the leafstalk. Hassler's Paraguayan specimens are almost wholly glabrous, but similar plants from southern Mato Grosso (e.g. Hatschbach 33094, NY) have dorsally pilosulous leaflets. The flower and pod are exactly those of var. silvestris. On upper Rio Apa that marks the Brazil-Paraguay frontier var. guaranitica is sympatric or almost so with subsp. bifaria var. unifaria, instantly distinguished by its densely yellowish-pubescent, alveolate-reticulate leaflets and coarsly veiny pod.

Distribution

Mato Grosso Brazil South America| Paraguay South America|